topic i.MX28 Power and Crystal problem in i.MX Processors https://community.nxp.com/t5/i-MX-Processors/i-MX28-Power-and-Crystal-problem/m-p/359322#M50470 <HTML><HEAD></HEAD><BODY><P>Hi all,</P><P>I'm currently debbuging a custom board based on the imx28evk schematic using an i.MX287. I'm using u-boot 2014-07 on a SD Card, and everything work fine on the imx28evk.</P><P></P><P>On my custom board, u-boot is not working, but i'm able to print debug info from spl_boot.c. After that, nothing. The baudrate on the DUART is around 100000 bauds on my board instead of 115200 on the evk (with the same sd card).</P><P></P><P>After reviewing my schematic, i've found that VDDIO33_EMI is connected to VDDIO_1V8 instead of VDDIO_3V3. Since this trace is under the imx28, I would like to confirm that my problems are related to this before making a new board.</P><P></P><P>When I probe the VDDIO_3V3 and VDDIO_1V8 rails, I measure a clean 3.3V and 1.8V. On the VDDIO33_EMI pin, I measure 1.8V. I can't find info in the datasheets about the difference between VDDIO33_x pins and VDDIO33_EMI pin. Are they link together internally?</P><P></P><P>The VDD4P2 linreg seems to start, but fall to 0V after 1s. My board is powered only by a 5V reg and the LI-ON_BATTERY net is not connected to an external regulator.</P><P></P><P>When I boot the EVK without the SD Card and I probe the crystal, I can see a clean 24MHz with a 500mVDC offset. When I boot my custom board (without the SD card), I see a flat 1VDC for about 2s, and then only 500mVDC. I'm using a C0603C180J5GACTU crystal (which seem very similar to the one on the evk: CS10-24.000MABJ-UT) with 18pf capacitors.</P><P></P><P>Do you think that all thoses issues are related to the VDDIO33_EMI wrong connection?</P><P></P><P>Thanks for you help.</P></BODY></HTML> Thu, 14 Aug 2014 15:39:41 GMT spicard 2014-08-14T15:39:41Z i.MX28 Power and Crystal problem https://community.nxp.com/t5/i-MX-Processors/i-MX28-Power-and-Crystal-problem/m-p/359322#M50470 <HTML><HEAD></HEAD><BODY><P>Hi all,</P><P>I'm currently debbuging a custom board based on the imx28evk schematic using an i.MX287. I'm using u-boot 2014-07 on a SD Card, and everything work fine on the imx28evk.</P><P></P><P>On my custom board, u-boot is not working, but i'm able to print debug info from spl_boot.c. After that, nothing. The baudrate on the DUART is around 100000 bauds on my board instead of 115200 on the evk (with the same sd card).</P><P></P><P>After reviewing my schematic, i've found that VDDIO33_EMI is connected to VDDIO_1V8 instead of VDDIO_3V3. Since this trace is under the imx28, I would like to confirm that my problems are related to this before making a new board.</P><P></P><P>When I probe the VDDIO_3V3 and VDDIO_1V8 rails, I measure a clean 3.3V and 1.8V. On the VDDIO33_EMI pin, I measure 1.8V. I can't find info in the datasheets about the difference between VDDIO33_x pins and VDDIO33_EMI pin. Are they link together internally?</P><P></P><P>The VDD4P2 linreg seems to start, but fall to 0V after 1s. My board is powered only by a 5V reg and the LI-ON_BATTERY net is not connected to an external regulator.</P><P></P><P>When I boot the EVK without the SD Card and I probe the crystal, I can see a clean 24MHz with a 500mVDC offset. When I boot my custom board (without the SD card), I see a flat 1VDC for about 2s, and then only 500mVDC. I'm using a C0603C180J5GACTU crystal (which seem very similar to the one on the evk: CS10-24.000MABJ-UT) with 18pf capacitors.</P><P></P><P>Do you think that all thoses issues are related to the VDDIO33_EMI wrong connection?</P><P></P><P>Thanks for you help.</P></BODY></HTML> Thu, 14 Aug 2014 15:39:41 GMT https://community.nxp.com/t5/i-MX-Processors/i-MX28-Power-and-Crystal-problem/m-p/359322#M50470 spicard 2014-08-14T15:39:41Z Re: i.MX28 Power and Crystal problem https://community.nxp.com/t5/i-MX-Processors/i-MX28-Power-and-Crystal-problem/m-p/359323#M50471 <HTML><HEAD></HEAD><BODY><P>IMX28 VDDIO33 must be in range 3.0 - 3.6 V.</P><P>Please try to provide it - at least - as first step.</P><P><BR />Have a great day,<BR />Yuri</P><P></P><P>-----------------------------------------------------------------------------------------------------------------------<BR />Note: If this post answers your question, please click the Correct Answer button. Thank you!<BR />-----------------------------------------------------------------------------------------------------------------------</P></BODY></HTML> Fri, 15 Aug 2014 00:42:31 GMT https://community.nxp.com/t5/i-MX-Processors/i-MX28-Power-and-Crystal-problem/m-p/359323#M50471 Yuri 2014-08-15T00:42:31Z